A PHP Error was encountered

Severity: Notice

Message: Use of undefined constant tracking_url_decode - assumed 'tracking_url_decode'

Filename: controllers/Ref.php

Line Number: 31

Backtrace:

File: /var/www/vhosts/enjoycuba.travel/httpdocs/application/controllers/Ref.php
Line: 31
Function: _error_handler

File: /var/www/vhosts/enjoycuba.travel/httpdocs/index.php
Line: 315
Function: require_once